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Log4J out to console and file produces warnings/errors log4j:WARN File option not set for appender

I'd like to integrate Log4J logging into my Java application, writing information out to a log file as well as displaying the info at the console. Unfortunately, I've had some trouble getting this off the ground. I'm working with Eclipse Juno on Win 7.
My log4j.properties file:
#configure logfile
log4j.appender.logfile = org.apache.log4j.RollingFileAppender
log4j.appedner.logfile.File = MyAppLog.log
log4j.appender.logfile.Append = true
log4j.appender.logfile.layout = org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern = %-5p %d [%t][%F:%L] : %m%n
#configure stdout
log4j.appender.stdout = org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target = System.out
log4j.appender.stdout.layout = org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern = %-5p %d [%t][%F:%L] : %m%n
log4j.rootLogger = debug, logfile, stdout
I belive the above follows the pattern of some other accepted answers on this topic.
I've specifed the location of this log4j.properties file wtih a VM argument:
-Dlog4j.configuration=file:///${workspace_loc}\path\to\file\log4j.properties
I instantiate the logger in my java class:
static Logger logger = Logger.getLogger(MyApp.class.getName());
log a string:
logger.info("barfoo");
This configuration results in the following warnings/errors on launch:
log4j:WARN File option not set for appender [logfile].
log4j:WARN Are you using FileAppender instead of ConsoleAppender?
log4j:ERROR No output stream or file set for the appender named [logfile]
It does not produce the log file. The console logging seems to be working just fine, however.

This will sound stupid - you have a typo. You have log4j.appedner.logfile.File instead of log4j.appender.logfile.File (note the 'n' and 'd' are switched). This is why it's complaining that you haven't set the File.

Issue with log4j log not writing to file

Does anyone see why this log is not writing to file. It is writing to standard out twice but not to the file:
Also, I tried removing the "Stdout" appender and then I don't get any logging at all.
package org.berlin.wicket;
import org.apache.log4j.Logger;
private static final Logger LOG = Logger.getLogger(QuickstartPage.class);
LOG.info("Loading constructor");
log4j.rootLogger=DEBUG,Stdout,mainAppender
log4j.appender.Stdout=org.apache.log4j.ConsoleAppender
log4j.appender.Stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.Stdout.layout.conversionPattern=%-5p - %-26.26c{1} -
%m\n
log4j.appender.mainAppender=org.apache.log4j.DailyRollingFileAppender
log4j.appender.mainAppender.file=logs/core.log
log4j.appender.mainAppender.datePattern='.'yyyy-MM-dd
log4j.appender.mainAppender.append=true
log4j.appender.mainAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.mainAppender.layout.ConversionPattern=[%d{MM/dd/yyyy
HH:mm:ss.SSS}] [%C{1}.%M():%L] [%t] [%p] - %m%n
log4j.logger.org.berlin=DEBUG,Stdout,mainAppender

You have two loggers which use the same appender (Stdout), hence why you see entries on the console twice.
As others have mentioned, the properties are case-sensitive, hence why your file appender is not configured correctly.

The File and Append properties are case senstive.
log4j.appender.mainAppender.File=someFileName.log
log4j.appender.mainAppender.Append=true

You should create an instance of FileHandler that writes log to a file called myfile.log.
FileHandler fileHandler = new FileHandler("myfile.log", true);
logger.addHandler(fileHandler);

Java Log4j overwrite output of FileAppenders

I am using Log4j for logging output of my application.
The log4j.properties files contents the following:
log4j.logger.DEFAULT_LOGGER=INFO,main_log, stdout
log4j.additivity.DEFAULT_LOGGER = false
# Direct log messages to a log file
log4j.appender.main_log=org.apache.log4j.FileAppender
log4j.appender.main_log.File=mainLog.log
log4j.appender.main_log.layout=org.apache.log4j.PatternLayout
log4j.appender.main_log.layout.ConversionPattern=%d{yyyy mm dd HH:mm:ss} %5p %c{1}:%L - %m%n
# Direct log messages to stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy mm dd HH:mm:ss} %5p %c{1}:%L - %m%n
Currently the following happens. When I start my main method where I call
static Logger log = Logger.getLogger("DEFAULT_LOGGER");
log.fatal("Process Logger");
it prints the output to stdout and file.log, which is fine. But when I start my application a second time it adds the output to the existing file. But I want to overwrite the log file. Is this possible? (I dont want to use Java for deleting, also I dont want to delete it manually of course) Is there an option in Log4J to tell the logger is to overwrite or the add output?

You need to use RollingFileAppender for this.
Check following SO questions on similar lines:
Post One
Post Two

You can use FileAppender, add log4j.appender.fileAppender.Append=false property to it

configure log4j to log to custom file at runtime

Can anyone please guide me as to how I can configure log4j to log to a specific file that I specify at run-time.The name and path of the log file are generated at run-time and the application must log to that particular file.
Generally file appender entries in the log4j.properties file points to the log file that will be used by the application.However in this case I would like to read the log file path from the command line and log to that particular file.
How can I achieve this ?

You can also do this from the log4j.properties file. Using the sample file below I have added the system property ${logfile.name}:
# logfile is set to be a RollingFileAppender
log4j.appender.logfile=org.apache.log4j.RollingFileAppender
log4j.appender.logfile.File=${logfile.name}
log4j.appender.logfile.MaxFileSize=10MB
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=[%-5p]%d{yyyyMMdd#HH\:mm\:ss,SSS}\:%c - %m%n
The log file name can then be set two different ways:
As a command line, system property passed to java "-Dlogfile.name={logfile}"
In the java program directly by setting a system property (BEFORE you make any calls to log4j).
System.setProperty("logfile.name","some path/logfile name string");

Adapted from the log4j documentation:
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.apache.log4j.SimpleLayout;
import org.apache.log4j.FileAppender;
public class SimpandFile {
static Logger logger = Logger.getLogger(SimpandFile.class);
public static void main(String args[]) {
// setting up a FileAppender dynamically...
SimpleLayout layout = new SimpleLayout();
FileAppender appender = new FileAppender(layout,"your filename",false);
logger.addAppender(appender);
logger.setLevel((Level) Level.DEBUG);
logger.debug("Here is some DEBUG");
logger.info("Here is some INFO");
logger.warn("Here is some WARN");
logger.error("Here is some ERROR");
logger.fatal("Here is some FATAL");
}
}

Can be also done by this properties define in log4j.properties file
log4j.appender.logfile=org.apache.log4j.RollingFileAppender
log4j.appender.logfile.maxFileSize=5000KB
log4j.appender.logfile.maxBackupIndex=5
log4j.appender.logfile.File=/WebSphere/AppServer/profiles/Custom01/error.log
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss,SSS} %5p [%t] %C %M %c{1}:%L - %m%n

Working and same has been tested
// setting up a FileAppender dynamically...
SimpleLayout layout = new SimpleLayout();
RollingFileAppender appender = new RollingFileAppender(layout,"file-name_with_location",true);
appender.setMaxFileSize("20MB");
logger.addAppender(appender);

Just remove your log4j code and replace this code in your java class it's working good no need to add properties or xml file
SimpleDateFormat dateFormatsd = new SimpleDateFormat("dd-MM-yyyy-hh-mm");
String dateandtime=dateFormatsd.format(new Date());
SimpleLayout layout = new SimpleLayout();
RollingFileAppender appender = new RollingFileAppender(layout,".\\Logs\\log "+dateandtime+".txt",true);
appender.setMaxFileSize("20MB");
logger.addAppender(appender);
The above code will log the logs for every minute.
Thanks

Java Logger only to file, no screen output

I have quite a simple problem but can't find a solution for it.
I have a logger with a file handler added, but it still spams the hell out of my console.
How could I get the logger to solely route all output to a file, with NO console outputs?

Old question but to help other developers:
You can also just use logger.setUseParentHandlers(false) on your logger.

The simplest way to guarantee that nothing will be written to the console is to put:
java.util.logging.ConsoleHandler.level = NONE
in your logging configuration file.

Remove all handlers (using Logger.getHandlers() and calling Logger.removeHandler() for each handler) from the root logger before adding your file handler.

Use log4j with
import org.apache.log4j.Logger;
Logger logger = Logger.getLogger("com.whatever");
PropertyConfigurator.configure("file-log4j.properties");
and set your display levels in file-log4j.properties:
# Root logger option
log4j.rootLogger=INFO, file
# Direct log messages to a log file
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=index-service.log
log4j.appender.file.MaxFileSize=1MB
log4j.appender.file.MaxBackupIndex=1
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
log4j.appender.file.Append=false

I use:
Logger logger = Logger.getLogger("MyLog");
Logger parentLog= logger.getParent();
if (parentLog!=null&&parentLog.getHandlers().length>0) parentLog.removeHandler(parentLog.getHandlers()[0]);